Facial expression of humanlike agent does not perfectly follow that of human beings. Such imperfection sometimes elicits negative impressions (e.g. uncanny valley). We proposed the brain function model in qualitative description, based on the framework of "Prediction Error." In our model, the predictive movement was processed with the internal model in the cerebellum and compared with perceived movement. The validation of our model was assessed in that the function of prediction had an essential role in the negative emotional response.